General Plan Update - City of Inglewood

Chapter 3 Infrastructure
There are a number of rivers in the Southern California region, but the river with the best
recorded history is the Los Angeles River. The flood history of the Los Angeles River is
generally indicative of the flood history of much of Southern California. While the City of
Inglewood is ten miles to the southwest of downtown Los Angeles, it is not so far away
as to not be affected by the heavy rains that bring flooding to Los Angeles.
The Santa Monica, Santa Susana, and Vertigo mountains, which surround three sides of
the valley, seldom reach heights above three thousand feet. The western San Gabriel
Mountains, in contrast, have elevations of more than seven thousand feet. These higher
ridges often trap eastern-moving winter storms. Although downtown Los Angeles
averages just fifteen inches of rain a year, some mountain peaks in the San Gabriel’s
receive more than forty inches of precipitation annually.
The amount of paved roads and the geographic location of the city, adjacent to the
Baldwin and Rosecrans Hills to the north and east, and the principal location of
Inglewood within the coastal plain which slopes gently from the east to the southwest,
prevent the City from flooding. However, it is important that the City’s storm water
infrastructure is maintained in prime condition.
• Regulatory Setting
Federal Regulations
National Pollutant Discharge Elimination System
Established under the Clean Water Act, National Pollutant Discharge Elimination System
(NPDES) regulation protects receiving water quality through two primary objectives: (1)
effectively prohibit non-storm water discharges to the storm drain system, and (2)
reduces the discharge of pollutants to the storm drain system to the maximum extent
practicable through the implementation of control measures called "best management
practices" (BMPs). In California, federal and state NPDES regulations are enforced by
the State Water Resources Control Board (SWRCB), and nine regional water quality
control boards requiring certain facilities to file a Notice of Intent (NOI), and implement
a Storm Water Pollution Prevention Plan (SWPPP) to control storm water pollutants
(e.g., manufacture of asphalt, concrete, vitreous and steel products). The RWQCB has
also issued a Los Angeles Countywide Municipal NPDES Permit which requires all cities
in the County to implement a wide variety of activities under extensive programs to
remove pollutants from storm water/urban runoff. As a Permittee under the Countywide
NPDES Permit, the City of Inglewood adopted an ordinance to allow implementation of
the programs required by the Permit codified in the Inglewood Municipal Code as Article
15 of Chapter 9.
3.3-2
City of Inglewood General Plan Update Technical Background Report